Application of Soft Demodulation in LTE Physical Layer Downlink

In order to improve the transmission property of LTE system link, this paper proposes a soft demodulation scheme adopted in LTE physical layer downlink. By comparing with the traditional hard demodulation scheme in various modulation modes, the paper proposes the theoretical expressions of soft demodulation and hard demodulation, and further researches the influence of noise-signal ratio to bit error ratio. Theoretical analysis and simulation results show that soft demodulation can be better matched with Turbo decoded mode, effectively reduce bit error ratio, and can be effectively applied to the analytical study of LTE communication system.